Tweaked the three example diagrams

[MarciaRieferJohnston]

(1) EKS example:

• I used the short name for CloudWatch to match the other labels.
• I deleted the internet gateway since we rarely use this icon any more.

(2) Three-tier example:

• I moved up the VPC box's bottom edge so that the Availability Zone boxes extend below it as usual.
• I used the short name for Route 53 to match the other labels.
• I blurred the second instance icon to keep people from picking Photocopy or some other effect.
• I deleted the internet gateway.

(3) Serverless example:

• I used the short names for SageMaker and API Gateway to match the other labels.

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[MarciaRieferJohnston]

Notes:

• I like the big slide size, which gives people plenty of room for complex diagrams so that they won't resize icons or text.
• In the three-tier example, I like that we show a service icon inside the VPC to remind people that not all service icons go outside the box.
• What does "three-tier" mean? (And will it resonate with partners in parallel with "EKS" and "serverless"?)